//
//  ScanCode.m
//  AVFoundation_erweimademo
//
//  Created by xiao han on 2016/12/16.
//  Copyright © 2016年 xiao han. All rights reserved.
//

#import "ScanCode.h"
#import <AVFoundation/AVFoundation.h>
#define SelfW self.bounds.size.width
#define SelfH self.bounds.size.height
#define ScanLineH 30

@interface ScanCode ()<AVCaptureMetadataOutputObjectsDelegate> // 用于处理采集信息的代理
{
    AVCaptureSession *session; // 输入输出的中间桥梁
    
    CAGradientLayer *scanLayer;
    
    UIView *scanBox;
}

@end

@implementation ScanCode

- (instancetype)initWithFrame:(CGRect)frame
{
    if (self = [super initWithFrame:frame]) {
        
        [AVCaptureDevice requestAccessForMediaType:AVMediaTypeVideo completionHandler:^(BOOL granted) {
            if (granted) {
                dispatch_async(dispatch_get_main_queue(), ^{
                    [self loadScanSetting];
                });
            } else {
                NSLog(@"无权限访问相机");
            }
        }];

        
    }
    
    
    return self;
}
-(void)loadScanSetting{
    // 获取摄像设备
    AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    
    // 创建输入流
    AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:device error:nil];
    
    // 创建输出流
    AVCaptureMetadataOutput *output = [[AVCaptureMetadataOutput alloc]init];
    
    // 设置代理，在主线程里刷新
    [output setMetadataObjectsDelegate:self queue:dispatch_get_main_queue()];
    
    // 初始化链接对象
    session = [[AVCaptureSession alloc]init];
    
    // 高质量采集率
    [session setSessionPreset:AVCaptureSessionPresetHigh];
    
    [session addInput:input];
    [session addOutput:output];
    
    
    
    
    // 设置扫码支持的编码格式（如下设置条形码和二维码兼容）
    output.metadataObjectTypes = @[AVMetadataObjectTypeQRCode,AVMetadataObjectTypeEAN13Code,AVMetadataObjectTypeEAN8Code,AVMetadataObjectTypeCode128Code];
    
    // 实例化预览图层
    AVCaptureVideoPreviewLayer *layer = [AVCaptureVideoPreviewLayer layerWithSession:session];
    // 设置预览图层填充方式
    layer.videoGravity = AVLayerVideoGravityResizeAspectFill;
    layer.frame = self.layer.bounds;
    [self.layer insertSublayer:layer atIndex:0];
    UIView *maskView = [[UIView alloc]initWithFrame:CGRectMake(0, 0, SelfW,SelfH)];
    
    [maskView setBackgroundColor:[UIColor colorWithWhite:0 alpha:0.7]];
    
    [self addSubview:maskView];
    
    
    // 运用贝塞尔曲线配合CAShapeLayer
    
    UIBezierPath *path = [UIBezierPath bezierPathWithRect:CGRectMake(0, 0, SelfW, SelfH)];
    
    // MARK: circlePath 画圆
    // [path appendPath:[UIBezierPath bezierPathWithArcCenter:CGPointMake(SelfW / 2, 200) radius:100 startAngle:0 endAngle:2*M_PI clockwise:NO]];
    
    // MARK: roundRectanglePath 画矩形！
    [path appendPath:[[UIBezierPath bezierPathWithRoundedRect:CGRectMake(SelfW *0.2f, SelfH*0.35f, SelfW - SelfW*0.4f, SelfH - SelfH *0.7f) cornerRadius:0] bezierPathByReversingPath]];
    
    
    CAShapeLayer *shapeLayer = [CAShapeLayer layer];
    
    shapeLayer.path = path.CGPath;
    [maskView.layer setMask:shapeLayer];
    
    //[self setBackgroundColor:[UIColor colorWithWhite:0 alpha:0.7]];
    // 设置扫描范围
    // 注意，这个属性各个方向的取值范围为0-1，表示占layer层的长度比例，x对应的是距离左上角的垂直距离，y对应的是距离左上角的水平距离，w对应的是底部距离左上角的垂直距离，h对应的是最右边距离左上角的水平距离
    output.rectOfInterest = CGRectMake(0.2f, 0.2f, 0.6f, 0.6f);
    
    // 设置扫描框
    scanBox = [[UIView alloc]initWithFrame:CGRectMake(SelfW *0.2f, SelfH*0.35f, SelfW - SelfW*0.4f, SelfH - SelfH *0.7f)];
    
    scanBox.layer.borderColor = [UIColor greenColor].CGColor;
    scanBox.layer.borderWidth = 1.0f;
    [self addSubview:scanBox];
    
    
    // 扫描线
    scanLayer = [[CAGradientLayer alloc]init];
    scanLayer.frame = CGRectMake(0, 0, scanBox.bounds.size.width, 2);
    scanLayer.backgroundColor = [UIColor greenColor].CGColor;
    [scanBox.layer addSublayer:scanLayer];
    //        // 设置渐变颜色方向
    //        scanLayer.startPoint = CGPointMake(0, 0);
    //        scanLayer.endPoint = CGPointMake(0, 1);
    //        // 设定颜色组
    //        scanLayer.colors = @[(__bridge id)[UIColor clearColor].CGColor,(__bridge id)[UIColor greenColor].CGColor];
    
    
    NSTimer *timer = [NSTimer scheduledTimerWithTimeInterval:0.1f target:self selector:@selector(moveScanLayer:) userInfo:nil repeats:YES];
    [timer fire];
    // 开始捕获
    [session startRunning];
}
// 以上之后我们的UI上已经可以看到摄像头捕获的内容，只要实现代理中的方法，就可以完成二维码条形码的扫描：
-(void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection:(AVCaptureConnection *)connection{
    if (metadataObjects.count>0) {
        
        AVMetadataMachineReadableCodeObject * metadataObject = [metadataObjects objectAtIndex : 0 ];
        
        [session stopRunning];
     
        
        [scanLayer removeFromSuperlayer];
        
        if ([_delegate respondsToSelector:@selector(dataString:)])
        {
            [_delegate dataString:metadataObject.stringValue];
        }
        
    
        
    }
}

// 实现计时器方法moveScanLayer:

- (void)moveScanLayer:(NSTimer *)timer
{
    CGRect frame = scanLayer.frame;
    if (scanBox.frame.size.height < (scanLayer.frame.origin.y+2+ 5)) {
        frame.origin.y = -5;
        scanLayer.frame = frame;
    }else{
        frame.origin.y += 5;
        [UIView animateWithDuration:0.1 animations:^{
            scanLayer.frame = frame;
        }];
    }
    
    
}

@end
